Various treatment methods require the utilization of a vascular access device that is adapted to be connected to a patient's vascular system. Such connection is typically effected by introducing at least one portion of the vascular access device into the patient's vascular system. During the treatment method, the connection is ensured by fixation of at least one part of the vascular access device.
Despite safety measures such as the above-mentioned fixation, various causes such as, e.g., movements on the part of the patient may lead to an undesirable disconnection of the vascular access device from the patient's vascular system. Such a disconnection may lead to grave consequences for the patient due to a free flow of blood and should therefore be prevented in a maximum possible degree, or should at least be recognized and corrected as quickly as possible.
From the prior art, various apparatus and methods for recognizing such a disconnection are known.
Thus it is known from practice, for instance, to monitor medical apparatuses through structural/body sound measurements and to make use of changes in the propagation of sound in the apparatus (such as a blood tube system) or in the patient's body in order to detect a disconnection of the vascular access device from the patient's vascular system.
Further methods that are known from practice include the detection of humidity at the location of connection as effected by a leakage of blood.